I Know I Shouldn't
by demonkatgurl17
Summary: Peter comes over unannounced. Sequel to "Rude Awakening". Third in the "Painted" series.


As soon as the elevator door opened, Derek's eyes shot open, instantly awake. Quickly, he scrambled for his phone on the nightstand, checking it for missed messages and finding none. It was almost noon and anyone who had any business looking for him was either in school or would have at least called before showing up.

Which meant his uninvited visitor was probably Peter.

Though, when his uncle strode into view, Derek kind of wished it had been anyone else (like a hunter or one of the Alpha pack). He groaned and levered himself up onto an elbow, pulling the pillow shielding his crotch tighter against him, highly aware of the dried come on his belly.

"What do you want?" Derek growled, his body tensing more and more the closer Peter got. He did _not_ need this right now.

"Lost my wallet," Peter said, sparing his nephew a brief glance before scanning the room for signs of it.

"And you couldn't have just _called_ me?" Derek asked tersely, watching as Peter went over to the couch and flipped over cushions, coming up empty handed.

I _could_ have," Peter said as he dropped to a knee to check underneath the couch. "But after last night, I didn't think you'd have answered."

It was a fair argument―and a valid one. If Peter _had_ called, Derek probably would have ignored it to spite the older man. There were precious few things lately that got under his uncle's skin, so it was more than likely that Derek would have leapt at the chance to have something to dangle over Peter.

Apparently the couch was a no-go because Peter stood with an aggravated sigh and started walking towards the bed. The one that _Derek_ was on.

"It's not over here," Derek said aggressively, hoping to keep Peter a good distance away while he lay naked as a jaybird (and reeking like a whore house).

Thankfully, Peter did stop, rolling his eyes as he did, but he still craned his neck, visually searching the bed to confirm it for himself. He moved around it, maintaining at least six feet between him and Derek. A crease wrinkled Peter's forehead as he frowned, looking confused and upset.

"Then where the―"

The great ball of bedclothes in the corner caught his eye and he made a beeline for it, ripping into the pile and shaking out each sheet. He let a triumphant "aha!" when a black leather billfold fell out onto the concrete floor. Peter busied himself with rifling through it (as if Derek could have _possibly_ taken anything from it when he hadn't even _known_ where the damn thing was), ignoring the scattered sheets and everything else―which was good because the breeze coming in through the open window had blown the intoxicating musk of _sex_ and _Stiles_ and _Peter_ further into the room and the mixture flooded Derek's senses.

Derek's eyes slammed shut as arousal shot through him and his imagination played out again.

Peter holding Stiles down and _taking_ him, grinding their scents into the sheets―into _Derek's_ scent― until the raw smell of their passion blended together perfectly, as though Derek had been there himself, rutting and fucking and claiming…

Derek's cock thickened against the stained pillow and he dug his fingertips into the mattress and pillow, desperately fighting the urge to roll his hips up in search of friction. To make matters worse, Derek was highly aware of Peter's presence across the room and his heart rate skyrocketed when he heard Peter move away from the window and approach the bed.

"Well, as much as I like visiting, I suppose I'll let you get back to your beauty sleep. Though I'm a little surprised you slept in the bed so soon without letting it air out…" Peter trailed off, having stopped about a meter away from the bed.

There was no way his uncle could miss the thick haze of arousal and Derek knew it. Keeping his eyes shut tight, Derek forced himself to breath deep and slow, his jaw clenched tight against the wash of embarrassment that crashed through him. An uncomfortable silence filled the room as he waited for his uncle to laugh at him, make a scathing remark, to do _something_ besides stand there and draw out his suffering.

But nothing came.

After an excruciatingly long moment, he heard Peter step closer to the bed, right up to the edge. A dip in the mattress shocked Derek into opening his eyes, but the curious expression on his uncle's face crushed the biting threat that had been on the tip of his tongue.

Pure stubbornness kept Derek from jumping straight out of the bed when Peter gripped a corner of the pillow covering his lap.

They stayed like that for a moment, like Peter was waiting to see what Derek would do.

"May I?" Peter asked softly, tugging slightly on the corner to show his intent.

Derek swallowed roughly, unable to speak. Peter was too close, his scent invading Derek's space and making things worse. His cock throbbed between his legs and Derek hated himself for not being able to control his own goddamn body, for not being able to quiet the soft groan he made as he let Peter pull the pillow away, the fabric dragging across his sensitive foreskin.

Peter tossed the pillow away from the bed and it hit the floor with a dull 'plop'. Then he just stared at Derek's cock, his eyes roving over how the dark tip strained towards Derek's stomach. As the older man watched, a tiny dribble of precome slowly oozed from the slit down to where his foreskin puckered over the head.

Breathing shallow, Derek averted his gaze, ashamed that he was achingly hard for his _uncle _of all people. It wasn't like he'd never noticed before how casually sexy Peter was―in his teen years, there had been the occasional illicit wet dream, especially on the nights when thoughts of Kate were getting him surprisingly nowhere―but it wasn't like Derek had spent his waking moments _actively_ fantasizing about his uncle. That hardly mattered though when little snippets of long-forgotten dreams flashed through his mind as Peter stroked his thigh.

The fingers traced lightly up and down his skin, then up a little higher and down again, giving Derek every opportunity to say no, to push Peter away and end this before they couldn't take anything back. But there was a heat in Peter's eyes that Derek had never seen before (that he'd never thought he'd _ever_ see) and he wanted it to stay on him. He knew he shouldn't want this, to touch and taste Peter, but it had been a long time since _anyone_ had set his blood on fire this way and Peter was offering him the kind of release Derek hadn't allowed himself since before he became an Alpha.

Before Peter had_ taken_ that power from _Laura_.

Derek shut his eyes against another wave of shame that rolled through him, confusing him. _Fuck_, this was messed up on more levels than most wedding cakes had.

"Hey," Peter said softly, drawing Derek's attention back to his face and away from internally debating just how _bad_ it would be if he showed this kind of weakness to his psychotic uncle. "No strings, okay? Just this." The older man's hand finally slid up and wrapped loosely around Derek's cock.

There was no guile in Peter's intent ―at least in his words―and Derek made the leap of faith that he hoped he wouldn't regret.

Slowly, Derek eased back on the bed until he lay flat out on the mattress, his hands on resting either side of his hips. He would have been completely vulnerable to attack if it weren't for the way his whole body was still strung tight with apprehension.

But Peter made no retaliatory move towards the exposed column of his nephew's neck (though his eyes did wander over it momentarily, considering). He shifted on the edge of the bed, bringing his knee up onto the mattress so that his torso wasn't quite so awkwardly half-turned. Peter's grip on Derek's cock tightened as it slid up to the crown, drawing the foreskin up to cover it and exposing it a second later as he pulling the foreskin down all the way to bunch at the base. Peter licked his lips, wetting them before he leaned down and took as much of Derek's cock into his mouth as he could.

Derek choked off his groan.

He couldn't tear his eyes away from where his uncle's lips were wrapped around his cock, trapping it in tight, wet heat. His toes curled into the mattress when Peter set a fast rhythm, bobbing up and down, following every up stroke with a pump and twist of his hand that soon had Derek shaking from the effort of restraining himself from thrusting up into Peter's mouth.

The mischievous shine in Peter's eyes showed that his uncle knew _exactly_ what Derek wanted to do, but the older man just sucked harder, took him a little deeper, until Derek couldn't hold back his moans and cries anymore.

The moment that Derek started vocalizing his pleasure, Peter slid his hand from Derek's cock to his hip, tugging on it, urging his nephew to fuck his throat with hunger burning in his eyes.

After that, Derek stopped holding himself back.

His hips surged up, burying his cock deep into Peter's throat, fucking it in hard, fast strokes, hardly giving Peter time to breath, but his uncle just took the abuse, bracing his hands on the mattress on either side of Derek and kept his jaw open nice and wide

Derek's thrusts stuttered out of rhythm as his senses spiraled out of control: his cock sliding through slick heat, a firm tongue flicking and stroking his shaft and underside of his crown, the heady tang Peter's arousal pouring into his lungs with every breath, and beneath it all was the sharp scent of Stiles's come and sweat, mixing in with the smell of Peter and himself and it pushed Derek over the edge.

Derek's teeth gnashed together as he whined and writhed on the mattress, pinned to it by Peter's sudden grip on his hips, his uncle forcing them to stillness as he swallowed Derek's load with a groan of his own.

As Derek shuddered on the bed, coming down from his orgasm, Peter licked at his softening cock, cleaning it until Derek pushed weakly at his shoulder to stop. Peter sat up and looked Derek over, seeming pleased with the way his nephew was still a little out of breath.

Dazed, Derek drank in the sight of Peter's bruised and swollen lips, trying to commit the image to memory even as the redness faded before his eyes. Stiles's lips would have been red for hours had it been _his_ mouth wrapped around Derek's cock, but the thought was pushed out of Derek's mind as he was overcome once more by the scent of Peter's arousal. He watched, entranced, as his uncle unzipped his jeans and pulled out his own cock, the thick flesh springing free to slap against Peter's shirt-covered abdomen.

Still staring down at his nephew, Peter languidly stroked himself, the precome he was leaking slicking the way.

Tempted as Derek was to sit back and watch Peter fist himself, he felt obligated to help (and a little turned on by the thought of it despite how spent he was). He sat up and reached for Peter's cock, wrapping his hand around the aching flesh when Peter released moved his own out of the way.

It felt gorgeous in his hand— rock solid hardness sheathed in soft, supple foreskin, wet from the trickle of precome oozing out from Peter's slit. The angle was different from what he was used to, with Peter almost facing him, but the concept was the same, stroking up, twisting his wrist a bit as he reached the head and stroking back down, keeping his hand in a nice tight ring.

Peter didn't bother restraining himself like Derek had. He eagerly thrust up into his nephew's grip, sighing at the friction from a hand other than his own. As Peter got closer, Derek had a harder time keeping up with his movements, but the lack of sync didn't seem to matter to Peter, if the blissed out look on his face was any indication. The older man's eyes were closed as he reclined back onto his hands, rocking his hips faster and faster, his eyes snapping open and locking onto Derek's as he came with a soft growl.

Derek's nostrils flared at the sharp tang of Peter's come. The sticky slickness dribbled over the back of his hand, but Derek didn't stop stroking Peter until his uncle collapsed down to his elbows, his chest heaving in ragged breaths. Derek waited until he had Peter's full attention before he slowly licked the come off his hand, keeping his eyes locked on his uncle's bright blue ones, pleased when they darkened with a trace of arousal.

Smirking, Peter slid off the bed and stood, tucking himself back into his pants. The streaks of his drying come weren't too noticeable on his cream-colored shirt, but Derek could still pick out each and every obscene splatter.

Evidence of what they'd done.

Derek's breath hitched as he stared at them, simultaneously proud and ashamed that he'd help make them.

Before Derek could stop him, Peter leaned down and pressed his lips to Derek's in a soft, almost chaste kiss. And Derek allowed it, even pressed up and responded when Peter's tongue teased at his lips and begged for entrance because a part of him still ached for Peter's approval.

But then Peter was pulling away with a hum to admire how Derek's body was propped up and on display, naked with his lips parted wantonly. Peter briefly brushed his thumb across Derek's full lower lip before smiling at down at his nephew.

"Until next time," Peter murmured softly as he turned on his heel. There was a saunter in his walk as he made his way to the elevator without a backwards glance, leaving Derek alone in a loft that reeked of himself and Peter with a bare hint of Stiles.

Derek sat in stunned silence, frozen in place on the bed long after his uncle had left, even more confused and conflicted than he'd been before knowing Peter's touch.


End file.
